US2607798A - Process for the preparation of polyethylene glycol esters of benzyl acid phthalate - Google Patents

Description

Patented Aug. 19, 1952 raoosssron THE PREPARATION OF POLY- ETHYLENEIGLYGOL ESTERS OF BENZYL I ACID ,PHTHALAIE 'William E. Weesner, Webster Groves, Mo., as-

I signor to Monsanto Chemical Company, St.

Louis,-Mo.-, a corporation of Delaware No Drawing.

. 1. Thisin'v'ention relates to polyethylene glycol esters of 'benzyl acid phthalate having-"the formula V A @Q (I) wherein n is a whole number from-2 to 5 inelusive. Hereinafter theexpression polyethylene glycol esters of benzyl acidpphthalate is meant tov include only those esters as defined by the above-mentionediormula.

The novel polyethyleneglycol esters of benzyl acid phthalate of this invention are clear. essentially colorless liquids having a wide range of Application September 22, 1949, Serial No. 117,279

4Claims': (cl. zoo-4,75)

In a glass reactor equipped with a stirrer, thermometer and a water cooledcondenser, 148.0 g. of phthalic anhydride was heated with 53.3 g. of diethylene glycol to a temperature of about 130-140" C. and maintained at this temperature with constant agitation forabout. 1 hour. To

thereaction mixture thus obtainedwas added viscosities.dependentupon the particular. pol-yethylene glycol utilized. They havebeen found to have exceptional utility as plasticizers and extenders for various natural and synthetic resins, and in particular polyvinyl chloride resins and copolymers containing predominantly combined vinyl chloride as exemplified by copolymers containing 85-95% by weight of vinyl chloride and 15-5% by weight of vinyl acetate, vinylidine chloride, dimethyl maleate, dimethyl fumarate or methyl methacrylate.

Various procedures may be utilized in preparing the novel compounds of this invention. Preferably, however, they are prepared by reacting a 1 molecular proportion of a polyethylene glycol having the formula v HO(CI-IzCH2O)m--H wherein m. is a whole number from2 to 5 inclusive, with approximately 2 molecular proportions of phthalic anhydride at a temperature in the range of from about l00l50 C'., thereby forming a reaction mixture containing predomi nantly polyethylene glycol bis (acid phthalate);

To this reaction mixture is then added approxi-- mately 2 molecular proportions of benzyl chloride and 1 molecular proportion of an alkali metal carbonate, preferably potassium carbonate, and the reaction mixture heated to a temperature within the range of about 100-160 C., within which range it is held with continuous agitation until the reaction is complete, thereby forming a reaction mixture containing predominantly the polyethylene glycol ester of benzyl acid phthalate. The ester thus obtained may be purified according' to any of the convenient methods well known to those skilled in the art. For example, the

126.5 g. of benzyl chloride, andthen overa period of about 2 hours 69.7 g. of K2003 (99% assay) was added while maintaining a temperature in the range of about 100-110 C}. This reaction mass was;then heated to about 130-14 0 C. and maintained at this temperature with constant agitation' fora period of 6 hours. r

After the reaction was complete, the reaction mass was washed with water and a dilute solution Viscosity, poises at25 C. (approx) 129 -1716 EXAMPLE II V l Tr'iethylene glycol bis(benzyl phthdlate) Triethylene glycol bis(benzyl phth'alate) was prepared utilizing the following reactants under the same conditions as set forth in Example I:

148 1 g. phthalic anhydride 82.5 g. triethylene glycol 69.? g. KzCOs (99%) 126.5 g. benzyl chloride 205.8 g. of triethylene glycol bis(benzyl phthalate) was obtained having the following properties: I

N 1.5559 Sp. gr. 25/25 1.2095 Flash point, F m 510 Fire point, F 535 Viscosity, poises at 25 C. (approx) 11 Assay per cent 3 EXAMPLE III Tetraethyle ne glycol bis(benzy'l phthalate) Tetraethylene glycol bis(benzylphthalate) was prepared utilizing the following reactants under the same conditions as set forth in Example 296 g. phthalic anhydride 194 g. tetraethylene glycol 139.4 g. K2C'O3 (99%)" 253.0 g. benzyl chloride EXAMIPL'E IV Z/Zene glycol bis(b'enzyl 117itiicZcte) flexible at room temperature and at reduced temperatures. The non-fugitive nature of the novelesterspf this invention as plasticizers for substantially. 99% of their plasticizer content Pentaethylene glycol bis(benzyl phthalate) was prepared utilizing the following reactants under the 'same'conditions. as set forth in Example I: Y 1

74 g. phthalic anhydride I a 60 g. pentaethylene glycol g. K2CO3 (99%) 63.2 g. benzyl chloride The novel compounds of. this invention possess outstanding utility as non-fugitive plasticizers for polyvinyl chloride resins. In many'applications utilizing plasticized polyvinyl chloride compositions it is desirable thatthe plasticizer content of the plasticized composition be retained in the composition for exceptionally long periods of time under various conditions. For example, such plasticizersjshould possess low volatility and non-migratory properties, i. e., little or no tendency to leave the plasticizedpolyvinyl chloride composition 7 and enter or; attack another material, .for example, ,a synthetic resin surface which may come in contact with the plasticized polyvinyl chloride composition. Heretofore in such applications resinous type plasticizers have been utilized almost exclusively, possessing these desirable characteristics of low volatility'ffand non-migratory tendencies. ageneral rule; the ester type plasticizers have not been "found to be satisfactory in these respects. Resinous type plasticizers, however, are deficient'in several respects. They are exceptionally'difflcult to process or prepare and are generally highly colored.

Surprisingly, the novel compounds of this invention have been found to possess the advantageous characteristics of resinous non-migratory plasticizers heretofore used While avoiding the disadvantages thereof thereby permitting the prep'a ration of exceptionally permanentresinous compositions plasticized with easily prepared ester type plasticizers.

Such characteristics are illustratedby the properties of plasticized polyvinyl chloride compositions containing the novel esters of this invention, I

Compositions were prepared containing 100 parts by Weight of a polyvinyl chloride resin formed by the polymerization of vinyl chloride and parts by weight of the novel esters of this invention. The resin and plasticizer were intimately mixed and fluxed on a differential steel roll mill for 5 minutes at 160 C. When homogeneous compositions had been formed on the roll mill, the plasticized polyvinyl chloride compositions were sheeted off the roll mill. These compositions were then molded into 5 x 5" x .040 sheets under a pressure of 2,000 lbs. per square inch at a temperature of 160 C. The compositions were clear, substantially colorless, free from odor and leathery in hand. They were .C. for a period of '24 hours.

after being placed in a Freas circulating oven at The non-migratory-characteristics of the novel compounds of this'invention when utilized as plasticizers for polyvinyl chloride resins, was demonstrated by placing these compositions in contact with a plasticized cellulose nitrate film at a temperature of 50 C. under a pressure of 0.5 lbs. per square inch for a period of 3 days. After such a period of time in contact with the cellulose nitrate surface, the samples were removed and the cellulose nitrate surface examined. The cellulose nitrate surface in contact with the polyvinyl chloride compositions plasticized with the novel compounds of this invention was marred only to the extent of being marked, which was due more to pure physical contact between the two surfaces rather than an actual migration of the plasticizer. ing the simple esters heretofore used as plasticizers for polyvinyl chloride, under a similar migration test severely softened the cellulose nitrate surface indicating a considerable degree of migration of the ester type plasticizer from the polyvinyl chloride composition to the cellulose nitrate film. The abovedescribed results of the permanence and migration tests of compositions containing the novel compounds of this invention as plasticizers, clearly demonstate that these compounds are an extremely permanent, nonmigratory or non-fugitive type of plasticizer.

What is claimed is: v,

1. A process for the preparation of polyethylene glycol esters of benzyl acid phthalate having the formula .f'

wherein n 1s a whole number from 2 to 5 inclusive comprising reacting a 1 molecular proportion of a polyethylene glycol having the formula wherein m is ,a Whole number from 2 to 5 inclusive with approximately 2 molecular proportions of phthalic anhydride at atemperature in the range of from about l00-l50 C. thereby forming a reaction mixture containing predominantly a polyethylene glycol bis(acid phthalate), reacting the polyethylene glycol bis(acid phthal- 1 ate) therein with a mixture containing approximately 2 molecular proportions of benzyl chloride and approximately a '1 molecular proportion of an alkalimetal carbonate, while maintaining a temperature in the range of from about l00-160 C., and recovering therefrom said polyethylene glycol esters .of benzyl acid phthalate.

Polyvinyl chloride compositions contain- 2,607,798 5 6 2. A process as described in claim 1 wherein REFERENCES CITED the polyethylene glycol is diethylene glycol The following references are of record in the 3. A process as described in claim 1 wherein me of this patent: the polyethylene glycol is triethylene glycol.

4. A process as described in claim 1 wherein 5 UNITED STATES PATENTS the polyethylene glycol is pentaethylene glycol. Number Name Date WILLIAM E. WEESNER- 2,075,107 Frazier Mar. 30, 1937 2,293,775 Soday Aug. 25, 1942

Claims (1)

1. A PROCESS FOR THE PREPARATION OF POLYETHYLENE GLYCOL ESTER OF BENZYL ACID PHTHALATE HAVING THE FORMULA